The present Application is a National Phase Application of PCT/EP2005/003014 entitled, “Head Restraint; in Particular for a Motor Vehicle” filed on Mar. 22, 2005 which published under PCT Article 21(2) on Oct. 20, 2005 as WO 2005/097545 A1 in the German language, which claims priority to German Patent Application DE 10 2004 016 474.6 filed Mar. 31, 2004, the entire disclosure of which, including the specification and drawings, is expressly incorporated herein by reference.
The present invention relates to a head restraint for a vehicle seat. More specifically, the present invention relates to a head restraint wherein at least a portion of the head restraint moves from a use position toward the head of the seat occupant into a safety position in the event of an accident (i.e. an active head restraint).
German Publication No. DE 199 23 909 A1 discloses a head restraint according to the generic type. The disclosed head restraint comprises a basic body which is connected rigidly and/or height-adjustably to the backrest of the vehicle seat via retaining bars. The basic body is arranged in a padded segment of a trough-like design. In the event of an accident, the padded segment is moved in a translatory manner toward the head of the seat occupant to reduce the likelihood of a whiplash trauma. The force required for moving the basic body is produced by a spring, which is prestressed in the direction of displacement, within a telescopic guide device.
German Publication No. DE 39 00 495 A1 describes a further head restraint according to the generic type, in which a padded segment is configured to pivot forward in relation to the basic body about a fixed axis of rotation in the event of an accident. A spring-loaded piston/cylinder arrangement in conjunction with a supporting lever, in which arrangement the piston rod is coupled to the basic body in the region of the axis of rotation and the cylinder is coupled to the padded segment, serves as driving device.
Furthermore, German Publication No. DE 199 41 712 C1 discloses a head restraint, in which a shiftable padded element is connected to the basic body via a scissors-type mechanism, by means of which the padded element can be moved forward from a rest position into a use position.
There is a need for an active head restraint with an effective driving device of simple and compact construction.
One exemplary embodiment relates to an active head restraint having a driving device. The driving device includes at least two components which are movable with respect to each other under the action of a first force. At least one component has an oblique surface which acts on the other component and is inclined in relation to the direction of the first force and by means of which a second force which deviates from the first direction of force and can be transmitted to the head restraint can be produced. This can take place, for example, after release of a locking device retaining the components in an initial position.
According to an exemplary embodiment, only one of the components is equipped with a corresponding oblique surface. According to another exemplary embodiment, both components are equipped with oblique surfaces which act with each other and run parallel.
According to another exemplary embodiment, the head restraint is rotatably connected to the backrest of the vehicle seat via an articulated lever having a lever arm which extends on the other side of the axis of rotation and can be shifted rearward by the driving device. In such an embodiment, the head restraint can be moved as a whole toward the head of the seat occupant.
According to another exemplary embodiment, the head restraint has a basic body and a padded segment which can be shifted in relation to the latter toward the head of the seat occupant under the action of the driving device, since the mass which is to be accelerated is reduced in this design.
According to another exemplary embodiment, the components are movable relative to each other with sliding friction (i.e. are not provided with rolling bodies which roll on the oblique surfaces). By relying on sliding friction, the construction of the driving device is simplified. Furthermore, the sliding friction can be used in a specific manner to keep the head restraint frictionally in the safety position when this position is reached.
According to another exemplary embodiment, the relative movement between the components has a translatory (e.g., fore and aft, etc.) component. However, a rotation between the components may additionally also be provided. According to such an embodiment, the components can be set into rotation in relation to each other under the action of a first force, with a translatory relative movement of the components in the direction of the axis of rotation being producible by the oblique surface(s).
According to another exemplary embodiment, the driving device has at least three components which are movable with respect to one another and of which the central component is rotatable in relation to the other rotationally fixed components.
In the case of the two last-mentioned exemplary embodiments, the components may be advantageously arranged telescopically one inside another in the use position, the oblique surface(s) being arranged on the inner and/or outer radial surface of at least one component and being designed in the manner of a thread. A relatively compact construction of the driving device is thereby made possible.
According to another exemplary embodiment, the locking device may in principle act between the relatively movable components of the driving device. According to another exemplary embodiment, the padded element is locked directly to the basic body by the locking device. In such an embodiment, further spring means which are prestressed (e.g., tensioned, biased, loaded, etc.) in the direction of displacement directly between the basic body and padded element and which support the driving device can be provided.
According to another exemplary embodiment, the oblique surfaces are provided with a toothing by means of which the head restraint can be locked at least temporarily at the latest when the safety position is reached. Such an embodiment may be used if the friction between the components is not sufficient to hold the head restraint after the safety position is reached. The locking is preferably triggered by the head impacting against the head restraint and is subsequently cancelled again, with the head restraint being able to be moved back again back into the initial position by a spring after the locking is ended.
According to another exemplary embodiment, the first force can advantageously be produced by a mechanical or chemical energy store, for example springs, pyrotechnic drives or the like, arranged within the head restraint.
According to another exemplary embodiment, provision may be made for the first force and/or the force for unlocking the locking device to be produced at least partially in the vehicle seat by the inertia of the seat occupant. A device suitable for this purpose is described, for example in German Publication No. DE 10 2004 048 910, the complete disclosure of which is hereby incorporated by reference.
According to another exemplary embodiment, the first force and/or the force for unlocking the locking device can furthermore be brought about at least partially by an accident-induced shifting of the vehicle seat or of parts of the same relative to the vehicle body, or else by deformation of the vehicle body. For example, a belt tensioner is suitable for producing these forces.
According to another exemplary embodiment, force transmission means, which are designed, for example, as a Bowden cable, can be arranged between the force production site for the first force, which site is arranged in or on the other side of the vehicle seat, and the head restraint. According to another exemplary embodiment, linkages or hydraulic transmission means are likewise also suitable.
a is a side view of a vehicle seat with a head restraint according to an exemplary embodiment with the head restraint shown in a first position.
b is a side view of the vehicle seat and head restraint of
a is side sectional view of the head restraint of
b is a front sectional view of the head restraint of
c is a side sectional view of the head restraint of
d is a front sectional view of the head restraint of
a is a side view of a head restraint according to another exemplary embodiment and shown in a first position.
b is a side view of the head restraint of
a is perspective view a driving device insertable into the head restraint of
b is a perspective view of the driving device of
a and 1b show a vehicle seat 1 according to an exemplary embodiment. The vehicle seat 1 comprises a seat part 2 and a backrest 3 which is connected in an inclination-adjustable manner to the latter and is equipped with a head restraint 4. The paired retaining bars 5 of the head restraint 4 are pivotably connected to the backrest 3 in the upper backrest region via a joint 6, so that, in the event of an accident, the head restraint 4 can be pivoted by rotation of the retaining bars 5 in the joint 6 from a first or use position (shown in
The force required for this shifting is produced by a driving device 7 which in normal use is blocked by a locking device 8. The driving device 7 comprises a wedge-shaped first component 10 which is mounted in a vertical longitudinal guide 9 and has an oblique surface 11 which is inclined by an angle α in relation to the direction of force of a prestressed (e.g., tensioned, biased, loaded, etc.) spring 12. A second component 13 in the form of a lever arm 14, which is rigidly connected to the retaining bars 5 and extends on the other side of the joint 6 into the frame of the backrest 3, bears against the oblique surface 11. The locking device 8 is equipped with a displaceable bolt 15 which, in the blocking position, leads or otherwise extends through the longitudinal guide 9 into the first component 10 and locks the latter.
Referring to
Referring to
The front end surface 23 of the hollow cylinder 18 is provided with sawtooth-like oblique surfaces 11 which are distributed over the circumference of the same and which bear against the oblique surfaces 11′ of a congruently designed, second component 13, which is likewise designed as a hollow cylinder 18′ having an end surface 23′. The hollow cylinder 18′ is connected rigidly and therefore also in a rotationally fixed manner to the padded part 16.
Referring to
a and 4b show a head restraint 4 according to another exemplary embodiment. According to the embodiment illustrated, the padded segment 16 of the head restraint 4 is shifted in relation to the basic body 17 from the first or use position (shown in
a and 5b show a driving device 7 according to an exemplary embodiment. The driving device 7 is suitable for use as the driving device 7 described above with reference to
Suitably shaped oblique surfaces 11.2 protruding radially inward from the projections 25 engage in the outer, slotted-link-like oblique surfaces 11′ while the inner oblique surfaces 11 of the hollow cylinder 18 interact with congruent oblique surfaces 11.1 of the cylinder 26 which is hollowed out in the manner of a cup. In a manner similar to the embodiment illustrated in
In the first or use position (shown in
By rotating back the hollow cylinder 18, for example by means of a tool which can be passed through the head restraint 4 from the outside, the driving device 7 is brought into its starting position again, with the spring 12 being prestressed.
According to an exemplary embodiment, it is possible also to undertake the locking of the driving device 7, which locking can be released in the event of an accident, by means of a blocking device which directly prevents the rotation of hollow cylinder 18 and component 13.2 with respect to each other, for example by means of a bolt latching radially inward through the projection 25 into the hollow cylinder 18. However, by means of the locking device 8 which is advantageously used, acts in the axial direction and may comprise, for example, a rod 27 which is fitted fixedly onto the component 13.1, runs within the hollow cylinder 18 and penetrates the component 13.1 (shown in
According to various alternative embodiments, instead of a rotation, the oblique surfaces 11, 11′ may also be displaced linearly downward in relation to the congruently designed oblique surfaces 11.1, 11.2 in order to obtain the effect desired by the head restraint. According to still further alternative embodiments, the oblique surfaces 11, 11′ may be of curved design instead of planar design.
Referring to
Number | Date | Country | Kind |
---|---|---|---|
10 2004 016 474 | Mar 2004 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/EP2005/003014 | 3/22/2005 | WO | 00 | 9/29/2006 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2005/097545 | 10/20/2005 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
3112137 | Drenth | Nov 1963 | A |
4944554 | Gross et al. | Jul 1990 | A |
5738412 | Aufrere et al. | Apr 1998 | A |
5934750 | Fohl | Aug 1999 | A |
6213548 | Van Wynsberghe et al. | Apr 2001 | B1 |
6767064 | Veine et al. | Jul 2004 | B2 |
6805411 | Gramss et al. | Oct 2004 | B2 |
Number | Date | Country |
---|---|---|
39 00 495 | Jul 1990 | DE |
296 03 991 | Jul 1996 | DE |
296 09 786 | Jul 1996 | DE |
199 23 909 | Jan 2000 | DE |
199 41 712 | Oct 2000 | DE |
201 14 944 | Jan 2003 | DE |
10215137 | Aug 2003 | DE |
10 2004 016 474 | Aug 2005 | DE |
2403137 | Dec 2004 | GB |
403213480 | Sep 1991 | JP |
WO 0035707 | Jun 2000 | WO |
Number | Date | Country | |
---|---|---|---|
20080272631 A1 | Nov 2008 | US |